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Pass a data.frame column name to a function
...(x[,column])
}
fun1(df, "B", max)
Alternatively, using [[ also works for selecting a single column at a time:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 <- function(x, column){
max(x[[column]])
}
fun1(df, "B")
...
How to reshape data from long to wide format
...mes(df) <- unique(dat1$name)
df
sqldf package:
library(sqldf)
sqldf('SELECT name,
MAX(CASE WHEN numbers = 1 THEN value ELSE NULL END) x1,
MAX(CASE WHEN numbers = 2 THEN value ELSE NULL END) x2,
MAX(CASE WHEN numbers = 3 THEN value ELSE NULL END) x3,
MAX(CASE WHEN numbe...
Split output of command by columns using Bash?
...d> | while read a b; do echo $a; done
The first parameter to read, a, selects the first column, and if there is more, everything else will be put in b. As a result, you never need more variables than the number of your column +1.
So,
while read a b c d; do echo $c; done
will then output th...
Cannot open backup device. Operating System error 5
...
Go to the SQL server folder in start menu and click configuration tools
Select SQL Server configuration manager
On SQL server services, on the desired instance change the (Log On as) to local system
share
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Algorithm to implement a word cloud like Wordle
...ou color and size words based on different weightings and it supports word selection (from a coordinate) and selected word highlighting. The source is yours to use as you see fit.
share
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improve...
Segue to another storyboard?
...;
// Load the initial view controller from the storyboard.
// Set this by selecting 'Is Initial View Controller' on the appropriate view controller in the storyboard.
UIViewController *theInitialViewController = [secondStoryBoard instantiateInitialViewController];
//
// **OR**
//
// Load the view...
RegEx: Grabbing values between quotation marks
... Please, why this works? I was using src="(.*)" but obviously it was selecting everything before the last ", your REGEX, though, selected only the src="" contents, but I didn't understand how?
– Lucas Bustamante
Jul 25 '18 at 23:25
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Is it possible to download an old APK for my app from Google Play?
... releases => Production (Manage Production) => Release history => Select the version that you want => Click on Download button.
Your account should be granted with full permissions, otherwise the download button will be hidden.
Original Answer
Go to
Developer Console => Ma...
Bash history without line numbers
...ply vertical whitespace or indenting at paragraph breaks, depending on the selected style."
$ history | awk ' $1=""; {print}'
clear
echo "In word processing and desktop publishing, a hard return or paragraph break indicates a new paragraph, to be distinguished from the soft return at the end of a...
How do I read text from the (windows) clipboard from python?
...r: from Tkinter import Tk [\nl] r = Tk() [\nl] result = r.selection_get(selection = "CLIPBOARD") [\nl] r.destroy()
– mgkrebbs
Jan 8 '14 at 0:42
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